Chakra Toasts can be rendered multiple times

[mbeckem]

Reproduction:

• Use multiple apps (or multiple instances of the same app) in a single html site
• Emit toasts in one of the apps (chakra's useToast(...))

Expected behavior:

• Toasts are rendered exactly once in the page

Actual behavior:

• Every toast is rendered multiple times (once in every app instance).

Analysis:

• Chakra uses a global store (in @chakra-ui/toast/toastStore) to manage toasts
• All applications render all toasts
• We either have to define that toasts are rendered locally (only for the "current" app) or globally in a shared container between all apps